As a fellow Apple Music subscriber, I regret to confirm the "Apple Music currently doesn't even get this right within the same album" as a common problem across all genres. :) My personal library really isn't very big, but it still shows what I call "metadata drift": you add an album that has 12 tracks, and eventually notice that while your library still contains those 12 songs, somehow there are now only six tracks on that album, with the other six tracks replaced by versions on various compilations (and if the data gods are feeling particularly mischievous, maybe a live version).